docs: def from_json(cls, data):
          """Create a Humidity Condition from a dictionary.
  
          Args:
              data = {
              "hum_type": string,
              "hum_value": float,
              "barometric_pressure": float,
              "schedule": string,
              "wet_bulb_range": string}
          """
          # Check required and optional keys
          required_keys = ('hum_type', 'hum_value')
          optional_keys = {'barometric_pressure': 101325,
                           'schedule': '', 'wet_bulb_range': ''}
          for key in required_keys:
              assert key in data, 'Required key "{}" is missing!'.format(key)
          for key, val in optional_keys.items():
              if key not in data:
                  data[key] = val
  
          return cls(data['hum_type'], data['hum_value'], data['barometric_pressure'],
                     data['schedule'], data['wet_bulb_range'])